Adjusted Gross Incomes. The Internal Revenue Service

(IRS) publishes data on adjusted gross incomes in Statistics of Income, Individual Income Tax Returns. The following relativefrequency histogram shows one year’s individual income tax returns for adjusted gross incomes of less than $50,000.

0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00 Relative frequency 0 10 20 30 40 Adjusted gross income

($1000s)

50 Use the histogram and the fact that adjusted gross incomes are expressed to the nearest whole dollar to answer each of the following questions.

a. Approximately what percentage of the individual income tax returns had an adjusted gross income between $10,000 and $19,999, inclusive?

b. Approximately what percentage had an adjusted gross income of less than $30,000?

c. The IRS reported that 89,928,000 individual income tax returns had an adjusted gross income of less than $50,000. Approximately how many had an adjusted gross income between $30,000 and

$49,999, inclusive?